This project was special to me because I ran the construction site myself with my fathers supervision (He’s a GC with a company in New York) working alongside my father and his crew was eye opening!

Now that my brother and I have the necessary knowledge and funding we are starting our real estate investing/rehab careers along side our construction company. 

That is something we do a lot in the Smokies, it's basically working alongside your realtor and a builder and putting everything in place for the end buyer to purchase a to-be-built home. 

I now rent out the old house (with the HELOC) and the rent comfortably covers the HELOC/mortgage payments with money to spare.My question is whether I am allowed to deduct the HELOC interest alongside my new mortgage interest on the new house.

Not sure how I, alongside many of my partners and fellow investors managed to do everything you said can't be done.

I am guessing traditional banks don't offer them alongside 20% down mortgages.

Same for AppFolio from contact with them.In terms of Accounting, I honestly have read that many people continue to use Quickbooks for accounting alongside Buildium and AppFolio.  

Don;t even call them similarly because if a seller does land on your buyers site and sees that you are affiliated, you will lose credibility as an honest actual cash buyer, even IF you DO buy houses in cash (along side wholesaling).It is easier to talk about the good language then it is about the bad language,But this is what I would say.ALWAYS make sense.

Also glad that your daughter is working along side with you. 

@Ian McDonald we invest in all of our deals as an LP along side our investors.